2012 Toyota Prius Vs Highlights
Toyota has recently added a new vehicle model to its growing collection of the Prius vehicles. This is part of the companys desire to increase the number of Prius models on the road that will be offered for sale to hybrid car finders. This time the 2012 Prius V with its V which is pronounced as vee for versatility was a redesigned version of this iconic Prius which remains to be the most fuel efficient hybrid car in the market.
One of the improvements that Toyota has placed on the 2012 Prius V is its reduced weight. This version takes pride of its reduced curb weight which is approximately 20 percent lighter than the previous version. Toyota has subjected the Prius V to diet which gave way for its final curb weight of about 3,274 lbs. With this particular characteristic, it is expected to deliver the same level of fuel-efficiency that would encourage more and more new car finders to purchase this version using the auto financing deals offered by Toyota dealerships.
The Prius V also offers more space compared to the previous version. Its current cargo space is about 34.3 cubic feet when its rear seats are folded making its space on this area 80 percent larger than what its closest competitors have.
However, this Prius still uses the Hybrid Synergy Drive system used in other Prius versions. This is powered by a 1.8liter Atkinson cycle engine with a 98 horsepower maximum power output. The second power source used in this hybrid is also the same Motor Generator 2 AC synchronous motor with a power output of about 80-horesepower used in previous Prius versions.
About the Author:
Marty Vergel Baes is an SEO Content Writer for three years now. He has been an expert in writing automotive related articles. Among the topics that he specializes on includes car buying guide, car maintenance tips, auto financing, and bad credit auto financing guides for http://www.carfinderservice.com/, http://aboutcar.com/ and http://www.autofinancing.net/. He is also good in conducting SEO research and article distribution with anchor texts on the body.
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the difference between Asynchronous and synchronous generator and advantages of both?
Wind Power: Why doesn’t a wind turbine with a synchronous generator need a gearbox?
As I understand it a wind turbine using a synchronous generator doesn’t need a gearbox since the problem with slow rotation at low wind speed is solved. But how does the synchronous generator solve it?
Speed of synchronous generator decrease with increasing load at output?
I have confusion as how increase in electrical load lead to decrease in generator rpm? And why if we increase the generator rpm (by injecting more fuel in gas turbines) increase the power? What is the influence of rotor and stator flux in this phenomenon?
The answer has to do with the way a generator works. A generator uses a ring of carbon brushes and a DC voltage supply from a control system called an exciter to generate a magnetic field on the rotating section. As the turbine spins the rotating section of the turbine passes by a stationary section that cuts through that magnetic field. creating a voltage. The magnetic field will naturally resist the turbine blades cutting through it which is why increasing the load, thus increasing the strength of the magnetic field, would cause a loss of rpm without putting more fuel to burn.
In reality once a generator is locked to the outside grid it will not change it’s rpm. It will always burn the amount of fuel required to keep it at 60 HZ (3600 rpm). The fuel just drives the turbine. Air is pulled in and compressed and then after going through the combustion section and mixing with the fuel is blasted across the turbine blades to spin them. Burning more fuel means you need more air to keep a proper mixture which forces more air across the blades which turns the turbine with more force. That is how if you had no resistance from the magnetic field you would increase the turbine rpm.
To answer the question about the rotor and stator. The rotor is the section of the turbine that has the magnetic field caused by the exciter, as it spins the stator cuts the magnetic lines of flux and induces the voltage that is sent out to your homes.
it could have a variable load/resistance circuit which optimises the blade speed to produce an averaged electricity output.In effect a single variable (electronically assited) gear.With data from the proposed site of the windmill and a good circuit design it can be very effecient,but has to be a ‘one off’ really.
By using a gearbox the turbine can have a better power /speed ratio ,enabling more efficiency at low wind speeds and more stable running at higher windspeeds .
By using an electro magnet in the generator windings ,rather than a fixed ferrite magnet ,the force of the ‘generator coil’ can be varied electronically ,i.e. when windspeed is low the electronics reduces the power to the generator feild windings(in effect an electro magnet) to decrease the mechanical resisitance and therfore keep the blade speed higher.As the blades spin faster the electronics allow more electricity to the feild windings to produce a stronger magnet (i.e. more power) but it can also use the electro magnetic effect of the coil windings as an electronic ‘brake’
I would assume that having a completly electronic system (other than voltage/current regulator)on a small wind generator would be a waste of money .
Smaller wind turbines usually mean higher rotor/bearing speeds and therfore more maintenance
The synchronous electric generator and motor. 10 points promised?
Who invented them? I can’t find it.
If nobody can find it, can they please tell me whether it was Tesla’s work that lead to the synchronous electric generator and motor? I know Tesla invented the induction motor and generator, and the synchronous machines are really a form of these. Just slightly changed.. If so, I can just say that.
Thanks in advance. 10 points for best answer.
In order to invent a DC generator with a commutator, it would have been necessary to realize that the current in a loop of wire rotating in a magnetic field changes direction as the loop rotates. A commutator is essentially a mechanical rectifier that rectifies the alternating current that is generated in the rotating wire coils and provides a rotating connection to conduct direct current away from the rotor. However, the developers of DC generators would have considered the alternating current in the rotor to be a problem to be solved rather than something useful. Once Tesla proved that alternating current was something useful, various approaches to building an AC generator would have been obvious to anyone who knew how to build a DC generator.
Wikipedia has a huge amount of information and lots of links from one article to another in Wikipedia as well as links to external sources. Most of the information is quite accurate, but there are errors and exaggerations. Here is a page of links to articles related to electric generators:
http://en.wikipedia.org/wiki/Category:Electrical_generators
How a synchronous generator practically work? what is the function of avr(automatic voltage regulator)in SG?
how the connection of avr to the generator made practically?
A synchronous generator is called “synchronous” because the waveform of the generated voltage is synchronized with the rotation of the generator. Each peak of the sinusoidal waveform corresponds to a physical position of the rotor. The frequency is exactly determined by the formula f = RPM x p / 120 where f is the frequency (Hz), RPM is the rotor speed (revolutions per minute) and p is the number of poles formed by the stator windings. A synchronous generator is essentially the same machine as a synchronous motor. The magnetic field of the rotor is supplied by direct current or permanent magnets.
The output frequency of an asynchronous generator is slightly (usually about 2 or 3%) lower than the frequency calculated from f = RPM x p / 120. If the RPM is held constant, the frequency varies depending on the power level. The peaks of the waveform have no fixed relationship with the rotor position. An asynchronous generator is essentially the same machine as an asynchronous or induction motor. The magnetic field of the rotor is supplied by the stator through electromagnetic induction.
The output frequency of a synchronous generator can be more easily regulated to remain at a constant value. Synchronous generators (large ones at least) are more efficient than asynchronous generators. Synchronous generators can more easily accommodate load power factor variations. Synchronous generators can be started by supplying the rotor field excitation from a battery. Permanent magnet synchronous generators require no rotor field excitation.
The construction of asynchronous generators is less complicated than the construction of synchronous generators. Asynchronous generators require no brushes and thus no brush maintenance. Asynchronous generators require relatively complicated electronic controllers. They are usually not started without an energized connection to an electric power grid, unless they are designed to work with a battery bank energy storage system. With an asynchronous generator and an electronic controller, the speed of the generator can be allowed to vary with the speed of the wind. The cost and performance of such a system is generally more attractive than the alternative systems using a synchronous generator.
The basic is Faraday’s Laws of Electromagnetic Induction. Whenever a conductor is moved in a magnetic field, an EMF is induced in that conductor and the magnitude of the EMF is directly proportional to the rate of change of flux.
In synchronous generators, this principle is used. We either keep the armature stationary and rotate the field or keep the field stationary and rotate the armature. Depending upon the speed of rotation and the strength of the magnetic field EMF is induced in the armature conductors.
Now, whenever the generator is loaded, due to increased current, the IZ drop inside the generator too increases and the terminal voltage falls. To improve the terminal voltage during rated load conditions, the field strength or excitation has to be increased. An AVR does this automatically. It receives feedback from the bus voltage; you set a reference voltage (that is – what voltage you want at full load conditions – from the generator). A comparator in the AVR compares this reference signal and the feedback signal; any error is amplified and fed to the control circuitry of the AVR. The AVR accordingly controls its output which is fed to the excitation circuit of the generator.